At last, a movie you can actually discuss afterward. And not just on Facebook or Twitter. No, you’ll want to chew it over in person, with friends, for hours.

When was the last time that happened?

The movie would be “The Social Network,” the highly anticipated collaboration between director David Fincher (“The Curious Case of Benjamin Button”) and screenwriter Aaron Sorkin (TV’s “West Wing”), which has its Friday night at the gala opening of the New York Film Festival at Lincoln Center. (The movie opens wide Oct. 1.)

The complex drama, about the founding of Facebook and the conflicting claims over who deserved credit for its invention, lives up to the hype. “Social Network” is smart, lively, well-acted and — this is key — raises questions and issues that are both timeless and totally of the moment.

Oh, sure, you probably spent time palavering after seeing “Inception” this summer, but that was trying to figure out just what the hell actually happened. How many dream levels were there again? And why were they mucking around in all that snow near the end?

In a way, “Social Network” seems almost a throwback to the great movies of the late 1960s and ‘70s. It taps into the zeitgeist. It’s about what’s happening now. Right now. And it has a viewpoint — well, actually, a bunch of them.

In the same way that “Bonnie and Clyde,” “Taxi Driver” and “The Godfather” were all provocative films, so is “Social Network.” Like those earlier movies (but without the torrent of bullets and actual blood), it raises questions about who’s good, what’s right and the definition of success in America.

“Social Network” begins in late 2003 with dweeby 19-year-old Harvard-ite Mark Zuckerberg (Jesse Eisenberg) getting dumped in a noisy bar by his girlfriend (Rooney Mara). He goes back to his dorm room, begins drinking and writes vicious hurtful things about her on his blog, including revealing her bra size. Classy guy.

Immediately afterward, on a tear, he hacks into the Harvard computer system and creates a site called Facemash. It features the faces of two female students side by side, and viewers are asked to rate which one is hotter. Within hours, the site has received more than 20,000 hits and crashes the Harvard server.

It’s Revenge of the Nerds, writ small. Soon it becomes Revenge of the Nerds, writ large.

Zuckerberg, socially inept but always the smartest guy in the room, goes on to conceive the idea for Facebook, the now global social network that has made him into the world’s youngest billionaire.

Or does he? Because success has many fathers while failure is an orphan, there are competing claims for Facebook’s founding. While no one argues that it was Zuckerberg’s brains and programming skills that built the system, he later faced legal challenges from other Harvard-ites who claimed they, too, had been there at the social network’s birth.

These competing claims, both in the deposition room and in flashback, make up the heart of the movie. One comes from Eduardo Saverin (Andrew Garfield), a fellow geek and Zuckerberg’s self-described best friend, who provides the seed money for Facebook. The second lawsuit is filed by Tyler and Cameron Winklevoss, twins who are everything that Zuckerberg and Saverin are not: socially skillful, preppy and successful athletes. (They rowed crew at Harvard and later in the Olympics.)

The Winklevoss twins claim that Zuckerberg ripped them off after, following the Facemash incident, they approached him about designing a dating website that would trade on the Harvard name. He, instead, strung them along, even as he was frantically building Facebook.

Basically, Zuckerberg, as written and portrayed here, is a brilliant jerk. He is so driven by his vision that it outweighs any social or ethical considerations. He creates the world’s most successful friend finder, but ends up friendless, just as he started.

There’s something very American about all this. Who owns an idea? Is it the person who first has it? The person who runs the farthest with it? The person who finances the dream rather than the dreamer? And what is the cost of success?

Those questions are timeless. The new ones “Social Network” also raises are about the internet and the speed with which it can spread information, both true and false. As the ex-girlfriend whom Zuckerberg so nastily disses in his early blog post later tells him when he tries belatedly to apologize, “The internet isn’t written in pencil, Mark. It’s written in ink.”

What I like most about the movie is that, without ever actually articulating them aloud, it raises all these questions about innovation, idea ownership, capitalism, friendship, loyalty and the reach and scope of the internet. They’re just there, existing almost as invisible subtitles in a viewer’s mind.

Even better, “Social Network” doesn’t provide easy answers to any of the questions it raises. Let the discussions begin.

(This review first appeared in conjunction with the New York Film Festival.)